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            <div><h4 class="title">
                <a name="asio.reference.strand.require"></a><a class="link" href="require.html" title="strand::require">strand::require</a>
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    <p>
        <a class="indexterm" name="asio.indexterm.strand.require"></a>
        Forward a requirement to the
        underlying executor.
    </p>
    <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <span class="identifier">Property</span><span class="special">&gt;</span>
<span class="identifier">constraint</span><span class="special">&lt;</span> <span
                class="identifier">can_require</span><span class="special">&lt;</span> <span
                class="keyword">const</span> <span class="identifier">Executor</span> <span
                class="special">&amp;,</span> <span class="identifier">Property</span> <span
                class="special">&gt;::</span><span class="identifier">value</span> <span
                class="special">&amp;&amp;!</span><span class="identifier">is_convertible</span><span class="special">&lt;</span> <span
                class="identifier">Property</span><span class="special">,</span> <span
                class="identifier">execution</span><span class="special">::</span><span
                class="identifier">blocking_t</span><span class="special">::</span><span
                class="identifier">always_t</span> <span class="special">&gt;::</span><span
                class="identifier">value</span><span class="special">,</span> <span
                class="identifier">strand</span><span class="special">&lt;</span> <span class="keyword">typename</span> <span
                class="identifier">decay</span><span class="special">&lt;</span> <span
                class="keyword">typename</span> <span class="identifier">require_result</span><span
                class="special">&lt;</span> <span class="keyword">const</span> <span class="identifier">Executor</span> <span
                class="special">&amp;,</span> <span class="identifier">Property</span> <span
                class="special">&gt;::</span><span class="identifier">type</span> <span
                class="special">&gt;::</span><span class="identifier">type</span> <span
                class="special">&gt;</span> <span class="special">&gt;::</span><span
                class="identifier">type</span> <span class="identifier">require</span><span class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">Property</span> <span class="special">&amp;</span> <span
                class="identifier">p</span><span class="special">)</span> <span class="keyword">const</span><span
                class="special">;</span>
</pre>
    <p>
        Do not call this function directly. It is intended for use with the <a class="link" href="../require.html"
                                                                               title="require"><code
            class="computeroutput"><span class="identifier">require</span></code></a>
        customisation point.
    </p>
    <p>
        For example:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">strand</span><span class="special">&lt;</span><span
            class="identifier">my_executor_type</span><span class="special">&gt;</span> <span
            class="identifier">ex1</span> <span class="special">=</span> <span class="special">...;</span>
<span class="keyword">auto</span> <span class="identifier">ex2</span> <span class="special">=</span> <span
                class="identifier">asio</span><span class="special">::</span><span
                class="identifier">require</span><span class="special">(</span><span class="identifier">ex1</span><span
                class="special">,</span>
    <span class="identifier">asio</span><span class="special">::</span><span class="identifier">execution</span><span
                class="special">::</span><span class="identifier">blocking</span><span class="special">.</span><span
                class="identifier">never</span><span class="special">);</span>
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            <div class="copyright-footer">Copyright © 2003-2022 Christopher M. Kohlhoff<p>
                Distributed under the Boost Software License, Version 1.0. (See accompanying
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